The A2 is indeed expensive compared to its competitors, excluding the A-Class, but it retains a high % of its original price after 3 years. This is something most people forget when buying their car. How else would you explain why people buy Daewoos, Hyundais, etc... they buy them for a couple of thousand cheaper than a Ford/Vauxhall etc, but after a year the car is worth half of what they paid for it. After 3 years, its worth maybe 20% of what they paid, and in 5 years its literally worth nothing... not to mention that these "cheap" cars often have very high servicing prices....
so look again at the A2... its expensive, yes, but it holds its value extremely well so you wont lose more than on another small hatchback, in fact probably less.. and the servicing intervals are extremely far apart, which makes it cheap to run the car... it's all in the maths of it, and this car doesnt work out as expensive to run!
personally i dont like it that much, theres something about the looks i like and something i cant quite put my finger on that puts me off... i cant figure out if i'd choose it over an A-class.. not that i'd want any of 'em!